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1.
PLoS One ; 17(11): e0278052, 2022.
Article in English | MEDLINE | ID: mdl-36413743

ABSTRACT

A meaningful engagement of learners is critical in the quality teaching and learning of mathematics at school level. Learner engagement has been an ongoing issue in mathematics classrooms in Nepal and elsewhere. In this context, this study aimed to examine the level of engagement (behavioral, social, emotional, and cognitive activities) and their association with learning mathematics through the virtual mode of instruction during the pandemic. The cross-sectional online survey design was employed among 402 secondary-level mathematics teachers in Nepal. Descriptive statistics, correlation, and structural equation modeling were the major statistical techniques used in research. The findings indicate that the level of behavioral, social, emotional, and cognitive engagement of students was found to be high in the online mode of instruction. Additionally, cognitive engagement has significant highest impact on social, behavior, and emotional engagement.


Subject(s)
COVID-19 , Pandemics , Humans , COVID-19/epidemiology , Cross-Sectional Studies , Social Participation , Mathematics , Cognition
2.
Bioorg Chem ; 126: 105877, 2022 09.
Article in English | MEDLINE | ID: mdl-35636126

ABSTRACT

A highly efficient domino [4 + 2] annulation process was employed to construct a novel indolizine chemical scaffold. Biological investigation led us to identify 6w as a potent anticancer agent. 6w significantly inhibited cell viability in BxPC3 pancreatic cancer, MCF7 breast cancer, and PC3 prostate cancer cell lines with IC50 values of 0.47 ± 0.04, 1.82 ± 0.08 and 2.68 ± 0.08 µM, respectively. Remarkably, 6w showed a weak effect on cell viability of nontumorigenic human keratinocyte cell line HaCaT compared to the above three types of cancer cells. 6w most potently inhibited cell viability of BxPC3 cells, and 6w also potently reduced cell migration and induced apoptosis in BxPC3 cells through activation of caspase-3 and cleavage of PARP in a dose-dependent manner. These results suggest that 6w can be used for the development of potential anticancer drugs for the treatment of pancreatic cancer.


Subject(s)
Antineoplastic Agents , Indolizines , Pancreatic Neoplasms , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Apoptosis , Cell Line, Tumor , Humans , Indolizines/pharmacology , Male , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms
4.
J Org Chem ; 86(15): 10235-10248, 2021 08 06.
Article in English | MEDLINE | ID: mdl-34292727

ABSTRACT

A domino Michael-aldol double elimination route to indolizines having two different acyl groups at the C5 and C7 positions is described where chromone is employed as a two-carbon unit for the synthesis of a pyridine moiety for the first time. Various analogues were readily accessed in good yields under metal-free and eco-friendly conditions. Further manipulation of the resulting products allowed entry to novel indolizine-heterocycle adducts, which are difficult to access by other methods.


Subject(s)
Chromones , Indolizines , Aldehydes , Pyridines
5.
ScientificWorldJournal ; 2021: 6649574, 2021.
Article in English | MEDLINE | ID: mdl-33994883

ABSTRACT

Garugapinnata Roxb. (Burseraceae) is a medium-sized tree widely available all over the tropical regions of Asia. Bryophyllum pinnatum (Lam) Oken. (Crassulaceae) is an indigenous and exotic plant grown in tropical regions. Both plants have been used for their anti-inflammatory, antioxidant, anticancer, wound healing, antidiabetic activities, etc. This investigation was designed to explore the result shown by methanolic extract of Garuga pinnata bark and Bryophyllum pinnatum leaves, on cognitive power and retention of the memory in experimental mice along with quantification of phenolic compounds and DPPH radicals neutralizing capacity. The memory-enhancing activity was determined by the elevated plus-maze method in Scopolamine-induced amnesic mice, using Piracetam as allopathic and Shankhpushpi as ayurvedic standard drugs. Two doses (200 and 400 mg/kg p.o.) of both extracts were administered to mice up to 8 consecutive days; transfer latency of individual group was recorded after 45 minutes and memory of the experienced things was examined after 1 day. DPPH assay method and the Folin-Ciocalteu method were employed to determine antioxidant potency and total phenol amount, respectively. 400 mg/kg of the methanolic B. pinnatum bark extract significantly improved memory and learning of mice with transfer latency (TL) of 32.75 s, which is comparable to that of standard Piracetam (21.78 s) and Shankhpushpi (27.83 s). Greater phenolic content was quantified in B. pinnatum bark extract (156.80 ± 0.33 µg GAE/mg dry extract) as well as the antioxidant potency (69.77% of free radical inhibition at the 100 µg/mL concentration). Our study proclaimed the scientific evidence for the memory-boosting effect of both plants.


Subject(s)
Amnesia/drug therapy , Antioxidants/pharmacology , Burseraceae/chemistry , Kalanchoe/chemistry , Nootropic Agents/pharmacology , Phytochemicals/pharmacology , Amnesia/chemically induced , Amnesia/physiopathology , Animals , Antioxidants/isolation & purification , Biphenyl Compounds/antagonists & inhibitors , Cognition/drug effects , Cognition/physiology , Female , Male , Maze Learning/drug effects , Maze Learning/physiology , Memory/drug effects , Memory/physiology , Mice , Nootropic Agents/isolation & purification , Phenols/pharmacology , Phytochemicals/isolation & purification , Picrates/antagonists & inhibitors , Piracetam/pharmacology , Plant Bark/chemistry , Plant Extracts/chemistry , Plant Leaves/chemistry , Plant Preparations/pharmacology , Scopolamine/administration & dosage
6.
Org Biomol Chem ; 18(40): 8119-8140, 2020 10 21.
Article in English | MEDLINE | ID: mdl-33016294

ABSTRACT

As a means to make new benzofuran-embedded polycyclic structures, we established two efficient one-pot sequential coupling routes to 2-amino-3-arylbenzofurans and 2-amino-3-arylnaphtho[2,1-b]furans. Further ring formation (six- and seven-membered rings) with the resulting amine moiety at the C2 position of benzofurans was realized, leading to further expansion of benzofuran-based chemical space.

7.
J Org Chem ; 85(16): 10994-11005, 2020 08 21.
Article in English | MEDLINE | ID: mdl-32674567

ABSTRACT

A highly efficient synthetic route to new quinone-indolizine hybrids was accomplished from quinones and N-substituted pyrrole-2-carboxaldehydes via a domino Michael addition-aldol condensation-aromatization sequence through which the central pyridine ring was constructed in atom-economical and environment-friendly manner. Post modification of the resulting products was also demonstrated, enabling further expansion of this heterocyclic chemical space. Biological evaluation of the quinone-indolizine hybrids revealed potent anticancer effects in human prostate adenocarcinoma cells (PC-3) and oral adenosquamous carcinoma cells (CAL-27).


Subject(s)
Indolizines , Benzoquinones , Humans , Molecular Structure , Quinones/pharmacology
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